Kanye West: MSG Concert Page Disappears ... Fans Panic!

Kanye West fans are going nuts -- the pre-sale ticket page for his "Waves" album release show mysteriously vanished Wednesday morning, but remain calm. It's gonna be okay.

American Express pre-sale tickets were scheduled to go on sale at 10 AM EST for the February 11 show, but Ticketmaster's site is showing a message saying the event no longer exists.

A source close to Kanye tells TMZ the event is still 100% on -- but it's still unclear what the issues are with Ticketmaster and the pre-sale. Tickets are also supposed to be sold at MSG on Thursday and to the general public on Friday ... but we'll see.

We've reached out to Ticketmaster and American Express ... so far, no word back.

Bottom line: Concert's happening ... but ticket sales seem up in the air.